154 



DR. IWAJI IKEDA. 



larger than the present species, as the hydrocaulus of the former is 

 said to be 2-3 inches (50-75 mm) long and 2 lines (4. 5 mm) thick 

 in the most swollen parts. As to the colouration of the hydrosome, 

 the present species differs remarkably from any of the species hitherto 

 known. The ground colour is light pink, as in some other species 

 e. g., C. nutans and C. pendula Ag." but differing in this respect 

 from C. carnea Clarkc 2) (coral-red) and also from C. nana Alder :i) 

 (white or yellowish). On the swollen part of the hypostome, on the 

 hydranth-basis, and along the boundary between the non-papillated 

 upper and the papillated lower regions of the hydrocaulus, a deep 

 pink colour with a yellowish tint is prominent. A fine streak of 

 the same color is found on the inner side of each proximal tentacle. 

 Numerous small round or elliptical spots of a light red colour are scat- 

 tered over the non-papillated region of the hydrocaulus, more thickly in 

 the lower half of this region. The general features and characteristic 

 color-markings of the hydrosome may be seen in fig. 1, which 

 represents one of the larger specimens drawn from life. Here it must 

 be noted that the proportion of the different regions of the hydroca- 

 ulus is not always the same as is shown in the figure But the figure 

 will give a fairly good idea of an average individual full)- expanded. 

 The filament-tuft borne by the proximal bulbous end of the hydroca- 

 ulus is represented in the figure in a greatly reduced state 



Hydranth. In the majority of the larger specimens the hydranth is 

 8-10 mm. in diameter at the base. The proximal tentacles, 38-40 in 

 number and 12-15 rnm. long, are arranged in a single circlet. In the 

 number of the tentacles the species agrees well with C . carnea. The 

 distal tentacles arc much shorter, more slender and more numerous 

 (about 70) than those just mentioned, and are arranged in 6-7 verti- 



1) Agassiz, — Contributions to the Natural History of the United States. (Vol. 4, 1862). 



2) Clarke, S. F., — The llydroids of Alaska (published by the Academy of Natural 

 Sciences in Philadelphia), 1872; An Alaskan Corymorpha-like Hydroid. (Proc. of the U. 

 S. Nat. Mus., vol. 26, 1903). 



3) Hincks, T., — A History of the British Hydroid Zoophyte. (London, 1868). 



